2026 Challenge Rules and Bugs

Fixed. Missing a 1 in the longitude column basically

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Getting the 6-digit locator on air is less error prone than the [lat, long] digits. Many of the 2m SSB/CW chasers near me have a minus sign in their longitude number. I don’t even know what ‘-’ is in Morse!

This is the chaser, so they should know where they are, but in this case too grid references were exchanged but the lat/long was entered instead.

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I wondered why anyone would go to that trouble, but I guess, depending on where within a gridsquare the contacts are, entering reasonably accurate lat/long instead of a 6-character gridsquare might just add a kilometre or two to the distance, and hence increase the score… :man_shrugging:

That would smack of desperation. Using an 8-digit locator would achieve that. For my home locator, 8 digits gets you almost on my house, where as 6 digits is in the nearby estuary. However, I thought I read that the software doesn’t handle 8-digit versions.

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It doesn’t. Only a 6 figure locator is supported because this is normally “good enough”.

Yes. And those who must be top-dog at any cost (you know who you are) will be considering doing this.

There would be much more profit in carrying a bigger beam!

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Is there anything that can be done to make you “tick a confirmation box” if you get a 2m/70cm SSB/CW over, say, 300km contact? I know some of these will be valid, but most will be an error.

I had one error the other week, typo on my part, but I now read/sense check all the distances in my logs after submission. It’s an extra step which most are probably not doing I suspect.

73
Gerald

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Me too, I deleted an entry last week due it clearly been an incorrect distance.
It’s easier with people or places that you are familiar with to spot errors, but some may not be so obvious.

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This one is though. Been there a while.
image
Callsign omitted to protect the guilty. Not hard to find though…

I emailed him about that today. It’s a chase, so might be a lat/long problem. If he doesn’t correct in a reasonable time, we can delete.

Elliott, K6EL

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Translated lat/long with incorrect sign on the longitude. Updated and fixed.

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First time chasing on monday with mycall/m. 6 digit maidenhead for exchange:

The qth in the log then was calculated as the utmost southwestern corner of the locator field. Usually the center of the field is used for distance-calculation in contests?

This small difference will be quite meaningless for the overall average of QSOs. In contest I do not have this choice anyway.

I could provide both formats in the exchange and tell the activator “Use that one, that is better for your score”.

So well?

Martin, OE3VBU

You are aware there are no winners, so the absolute score doesn’t matter?

You win by taking part :wink:

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But why is the southwestern corner used? It seems more logical to use the centre.

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Help those of us in the North East.

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I spent some time working up a proposal to use distance based scoring in VHF/UHF field contests in VK. This educated me somewhat on the terminology of the Maidenhead system. And also the error levels incurred by measuring from the corners or the middle of a subsquare.

A “field” represents the first 2 characters of the reference, eg QF. The world is divided into 18 x 18 fields that are 20 degrees longitude wide and 10 degrees of latitude “high”. the order of the characters is east-west first, north-south second. 20 x 18 =360 (number of degrees from any point around the world and back to that point, 18 x 10=180 (pole to pole).

Adding two digits divides the field into 100 areas called squares, each labelled with two digits from zero to 9. Eg QF44.

The area we commonly refer to as a grid square, with 6 characters defining it, is actually a sub-square. Eg. QF44 is a “square” and QF44MP is a subsquare and is about 4-5 km wide (measuring East-west) and 3 km “high” (North-south) in temperate latitudes. Closer to the equator the width increases and further from the equator the width decreases, with zero width at the geographical poles.
So the centre of QF44MP is at the intersection of QF44MP44, 45, 54 and 55. The digits only go from 0 to 9, which number represents the centre? None. The references define an area, not a line.

Note that what we refer to as a square or sub-square does not have parallel sides because they are curved, but the top and bottom edges of the squares are parallel. The commonly used Mercator projection makes maps flat but does not show the true shape.

So using a 6 character grid sub-square for location is approximate and has an error of up to 4 or 5 km laterally and an error in the north-south dimension of several km. Close enough for government work as they say. And more than adequate for ham radio.

Just musing over my morning coffee.

73 Andrew VK1DA/VK2DA

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We grow up with 2-D maps that use the Mercator projection not realising how it distorts sizes and distances the closer you get to the poles, e.g. Greenland looks as big as Africa, where as in reality it’s 14 times smaller than Africa. When you view the Arctic on a 3-D globe you realise how the distances between land masses are quite different.

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Like nearly everything, it’s based on how ASCII is interpreted in older instruction architectures and some good old fashioned integer truncation. A surprising number of implementations choose to follow that because it makes the maths easy and fast.

As Andrew VK1DA says, it’s not wrong as the corner is still part of the square. Over time, the errors should average out.

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Lucky I didn’t say anything about the dirty knife. hi

73 Martin

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